Grade 8 Hex Head Flange Bolts, often referred to as Frame Bolts, are high strength fasteners typically used on the frames of large trucks and heavy equipment. They feature a flange under the hex head that serves as an integrated high strength washer. This makes them ideal for use on vehicle frames where irregular or oversized holes may be encountered. The large integrated flange increases the bolts bearing surface and will distribute the bolt clamp load over a larger area for a more secure connection. Grade 8 Hex flange bolts meet the material requirements of SAE J429 and have a material tensile strength of 150,000 psi minimum. For a secure high-strength connection that resists loosening and vibration it is recommended that Grade 8 Hex Flange Bolts be used with Grade G Flange Style All-Metal Locking Nuts. Hex Flange Bolts have a Phosphate and Oil finish unless otherwise noted.